GEOMETALLURGY NEW IDEAS FOR MINING AND MINERAL PROCESSING AT LKAB

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1 GEOMETALLURGY NEW IDEAS FOR MINING AND MINERAL PROCESSING AT LKAB Dr. mont. Kari Niiranen, M. Sc. Specialist in Process Mineralogy LKAB, SWEDEN

2 Owned by the Swedish Government About employees (including temporaries) Narvik Harbour Kiruna Under ground mine and processing World-leading in pelletization for more than 50 years Production in 2016: 24.0 Mt pellets (DRpellets and blast furnace pellets) 2.9 Mt fines and special products Malmbanan Railway Narvik - Luleå Malmberget Under ground mine and processing Svappavaara Open pit mines and processing Luleå Harbour and Head Office IRON ORE OPERATIONS OF LKAB

3 GEOMETALLURGY Geometallurgy, in its basics, combines geological and metallurgical information to create a spatiallybased predictive model for mineral processing plant to be used in production management. (Lamberg, 2011)

4 GEOMETALLURGY The area of geometallurgy is in its context not entirely new but: Development of automated mineralogy technologies. New mines and more complex geology. Increased competition and environmental demands. has made it even more feasible today. From rock to finished product

5 FOCUS ON GEOMETALLURGY The area of geometallurgy is not a new area at LKAB, but it has become more important today because: More complex geology and mineralogy of iron ore deposits in Kiruna and Malmberget. Increased production at Kiruna mine: 22.3 Mt (in 2000) to 26.9 Mt (in 2016). Exploiting new iron ore deposits. Increased environmental demands - and competition.

6 THE FIRST IDEAS OF GEOMETALLURGY AT LKAB Oulu Mining Summit Leveäniemi open pit Mining plan Mining bock 10x10x10 m 3 Ornstein and Fagerberg (1962) had an idea to create a rough, preliminary forecast for the product outcome of beneficiation of the iron ore from the Leveäniemi deposit with help of the systematic macroscopic examination of drill cores.

7 THE FIRST IDEAS OF GEOMETALLURGY AT LKAB Oulu Mining Summit Bergström and Anttila (1973) made an attempt to compare the experimental results of grinding in the laboratory- and pilot-scale with the large scale operation to determine the energy efficiency of the mills, the energy consumption and to develop conversion factors.

8 THE PROJECT SILICA IN THE MINE In 2007 fluctuations and increase of SiO 2 grade in the crude ore in Kiruna. Problematic specially in the case of DR-pellets (LKAB DR Oxide Pellets). Develop a simplified method at the laboratory scale for predicting the physical properties of the ore at the mineral processing. Make a reliable prognosis for the SiO 2 grade in the crude ore and processing parameters for future mining. CRUDE ORE BENEFICIATION PELLETIZING DR PELLETS 67.9 % Fe 0.75 % SiO 2

9 SYSTEMATIC MINERAL PROCESSING TESTS AT LKAB S LABORATORY CRUSHING GRINDING SCREEN ANALYSIS DAVIS MAGNETIC TUBE CHEMICAL ASSAYS SPECIFIC SURFACE DENSITY LASER GRANULOMETER SIMULATION OF PARAMETERS Logging of drill cores Sampling ~ 3000 SAMPLES ~ 1815 ANALYSED DATABASE

10 SIMULATION OF PARAMETERS Y = X % SiO 2 in DT-conc. (lab) ± 0.04 % SiO 2 X = the percentage of SiO 2 in the Davis magnetic tube concentrate in the laboratory by P(80) = 45 µm = the difference between the mean of SiO 2 grade in the laboratory scale and at the concentration plant = characterizes empirical inaccuracy limit. E = A + τ B ± 0.47 kwh/t A = 5 kwh/t (constant). Τ = the retention time of the material in the laboratory ball mill. B = 0.65 kwh/t/minute (constant) kwh/t = characterizes empirical inaccuracy limit.

11 SIMULATION OF SiO 2 -GRADE IN THE MAGNETITE CONCENTRATE Oulu Mining Summit Sample Ore type Crude ore DT concentrate Fe % SiO 2 % DT_SiO 2 % 6252 B B B B B B

12 SILICATES IN THE ORE TYPE B2 B2 - a Oulu Mining Summit Actinolite Ca 2 (Mg,Fe) 5 SiO 8 O 22 (OH,F,Cl) 2 Phlogopite KMg 3 (Si 3 Al)O 10 (F,OH) 2 Quartz SiO 2 Titanite (Sphene) CaTiSiO 5 B2 - b Albite Na(AlSi 3 O 8 )

13 NEW 3D GEOLOGICAL AND BLOCK MODEL Oulu Mining Summit TONNAGE,GRADE (Fe, P, SiO 2,.) GEOLOGY ORE TYPES MINERALOGY B2-a, B2-b MINERAL PROCESSING PARAMETERS

14 IRON ORE DEPOSIT IN MALMBERGET ~ 20 separate ore bodies, of which 13 are currently mined. 95% magnetite och 5% hematite. Variations in Fe and P grades 49% - 63% Fe; % P ViRi magnetite, high V and Ti, low P Printzsköld magnetite, low V and Ti, high P

15 GEOLOGICAL AND MINERALOGICAL DATA FOR GEOMETALLURGICAL MODELLING Oulu Mining Summit (Lund 2013)

16 CLASSIFICATION FOR A GEOLOGICAL MODEL Classified ore body Ore type Sub-type GEM-type Texture Semi-massive Feldspar rich Fsp Schistose FABIAN Massive Amphibole rich Apatite rich Amph-(Ap-Bt) Ap-(Amph) Granoblastic, porphyroblastic, exsolution, lamellas Granoblastic, porphyroblastic, exsolution, lamellas PRINTZSKÖLD Semi-massive Feldspar rich Fsp Schistose Biotite rich Bt-(Amph-Ap) Schistose, granoblastic, porphyroblastic Massive Apatite rich Ap-(Amph) Granoblastic, porphyroblastic, exsolution, lamellas (Lund 2013)

17 LEVEÄNIEMI DEPOSIT The Leveäniemi open pit was operated between 1964 and 1981 and was reopened in Exploration drilling program carried out. No geometallurgical information available until Chemical assays, some rock mechanical data, some information about the mineralogy. PREP-project, co-operation with LTU (Photo: Fredric Alm) (PREP / LTU; Lishchuk / Koch)

18 GEOMETALLURGICAL PROJECT / LEVEÄNIEMI Geological data Sampling Test work Process model Simulation Geomet. model (PREP / LTU; Lishchuk / Koch)

19 A COURSE IN GEOMETALLURGY AT LKAB To create a common geometallurgical language within LKAB. Lectures, exercises and practical laboratory work in collaboration with Technical University of Luleå (Sweden) following LKAB s processes. Participants from different departments of LKAB. From mine to mill and from mill to finished product. Oulu Mining Summit

20 A REAL CHALLENGE DIFFERENT Fe-ORE TYPES KIRUNA MALMBERGET GRUVBERGET

21 SUMMARY The area of geometallurgy is not something entirely new at LKAB and we have worked according to the ideas from mine to mill and minerals to products for several years. The idea of geometallurgy at LKAB covers a broad area from the internal education to the instrumental side at the R&D Department. The projects of a great importance for new geometallurgical thinking at LKAB were the project Silica in the Mine and the mineralogical, chemical and textural characterization of the Malmberget iron ore deposit for a geometallurgical models. There are many new and interesting challenges for the experts and skilled personnel at LKAB to race with respect to the field of geometallurgy.

22 THANK YOUR FOR LISTENING! The geometallurgical Team of LKAB